1. **State the problem:** A grocery store sells canned corn at 5 cans for 2.19. Jonathan wants to buy 40 cans. We need to find the price $x$ for 40 cans using a proportion. 2. **Identify the correct proportion:** The price per can is constant, so the ratio of cans to price should be equal: $$\frac{5}{2.19} = \frac{40}{x}$$ 3. **Set up the equation:** $$\frac{5}{2.19} = \frac{40}{x}$$ 4. **Cross multiply:** $$5 \times x = 2.19 \times 40$$ 5. **Solve for $x$:** $$5x = 87.6$$ 6. **Divide both sides by 5:** $$\cancel{5}x = \frac{87.6}{\cancel{5}}$$ $$x = 17.52$$ 7. **Interpretation:** The price for 40 cans is 17.52. **Answer:** The correct proportion is option A: $$\frac{2.19}{5} = \frac{x}{40}$$